Preparation and Performance Analysis of Graphite Nanoparticle in Domestic Refrigerator

This article examines experimentally the performance of domestic refrigerators with isobutene (R600a) and graphite nano-lubricants as working fluids. Graphene has an extremely thin layer structure that fills the friction surfaces and reduces friction losses quickly. However, there is a lower coefficient of friction (COF) and higher thermal conductivity of nano-fluids generated using graphite in the base fluid. The graphite nanoparticles modified in the surface are verified to continuously suspend for a long period of time in the form of clusters. The refrigeration test examined the application of the graphite nano-lubricants in the domestic refrigerator with a volume concentration of 0.1%, 0.3%, and 0.5%. The findings show that nano-refrigerants in the refrigeration system work safely and normally. And also compressor and refrigerator output have been analyzed. Moreover, refrigerator energy usage decreased by 15.26%, 17.10%, and 21.16% with graphite nano-lubricant as a concentration of 0.1%, 0.3% and 0.5%, respectively.

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Thermodynamic Analysis of Heat and Mass Transfer Enhancement for R134a-DMAC/CNT Vapour Absorption Refrigeration System

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.592-594.1832 ◽

2014 ◽

Vol 592-594 ◽

pp. 1832-1836 ◽

Cited By ~ 2

Author(s):

A. Kathiravan ◽

E. Karthikeyan ◽

V. Mariappan ◽

Chidambaram T. Muthiah

Keyword(s):

Thermodynamic Analysis ◽

Volume Concentration ◽

Theoretical Study ◽

Absorption Refrigeration ◽

Refrigeration System ◽

Transfer Enhancement ◽

Mass Transfer Enhancement ◽

Nano Fluid ◽

Absorption Refrigeration System ◽

Nano Fluids

The objective of this paper is to study thermodynamic analysis of R134a-DMAC and R134a-DMAC/CNT vapour absorption system and compare this both system performance. This investigation for R134a-DMAC is carried out based on the correlations available in the literature. The change of thermophysical properties for R134a-DMAC/CNT is predicted and is incorporated in the pure R134a-DMAC correlations. The analysis is carried for 1 kW evaporator capacity and effectiveness of solution heat exchanger is taken as 0.8. Variations in the performance parameters of the system with and without nano fluids are studied against various operating temperatures of generator, absorber and different volume concentration. The result of this theoretical study shows that co-efficient of performance (COP) of system with CNT nano fluid is improved as well as the absorber capacity also increased due to enhanced heat transfer of nano fluids. It also observed that the performance achieved by the pure R134a-DMAC at the elevated generator temperature could be achieved at low generator temperature using R134a-DMAC/CNT.

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Thermodynamic and Energy Efficiency Analysis of a Domestic Refrigerator Using Al2O3 Nano-Refrigerant

Sustainability ◽

10.3390/su13105659 ◽

2021 ◽

Vol 13 (10) ◽

pp. 5659

Author(s):

Farhood Sarrafzadeh Javadi ◽

Rahman Saidur

Keyword(s):

Temperature Gradient ◽

Technological Changes ◽

Nanoparticle Concentration ◽

Evaporator Temperature ◽

Domestic Refrigerator ◽

The Past ◽

Nano Lubricant ◽

The Stability ◽

Energy Efficiency Analysis ◽

Al2o3 Nanofluid

Refrigeration systems have experienced massive technological changes in the past 50 years. Nanotechnology can lead to a promising technological leap in the refrigeration industry. Nano-refrigerant still remains unknown because of the complexity of the phase change process of the mixture including refrigerant, lubricant, and nanoparticle. In this study, the stability of Al2O3 nanofluid and the performance of a nano-refrigerant-based domestic refrigerator have been experimentally investigated, with the focus on the thermodynamic and energy approaches. It was found that by increasing the nanoparticle concentration, the stability of nano-lubricant was decreased and evaporator temperature gradient was increased. The average of the temperature gradient increment in the evaporator was 20.2% in case of using 0.1%-Al2O3. The results showed that the energy consumption of the refrigerator reduced around 2.69% when 0.1%-Al2O3 nanoparticle was added to the system.

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Modelling and performance study of a continuous adsorption refrigeration system driven by parabolic trough solar collector

Solar Energy ◽

10.1016/j.solener.2008.12.003 ◽

2009 ◽

Vol 83 (6) ◽

pp. 850-861 ◽

Cited By ~ 89

Author(s):

A. El Fadar ◽

A. Mimet ◽

M. Pérez-García

Keyword(s):

Solar Collector ◽

Refrigeration System ◽

Performance Study ◽

Parabolic Trough ◽

Adsorption Refrigeration ◽

Continuous Adsorption ◽

And Performance ◽

Parabolic Trough Solar Collector

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Thermoacoustic-Stirling Heat Pump for Domestic Applications

ASME 2010 3rd Joint US-European Fluids Engineering Summer Meeting: Volume 2, Fora ◽

10.1115/fedsm-icnmm2010-31150 ◽

2010 ◽

Cited By ~ 1

Author(s):

Srinivas Vanapalli ◽

M. E. H. Tijani ◽

Simon Spoelstra

Keyword(s):

Performance Analysis ◽

The Netherlands ◽

Heat Pump ◽

Linear Motor ◽

Energy Resources ◽

Coefficient Of Performance ◽

Energy Usage ◽

Domestic Heating ◽

Work Input ◽

And Performance

Domestic heating contributes to a significant amount of energy usage in the Netherlands. Due to scare energy resources, attention to develop new and efficient technologies is increasing. At ECN, a burner driven heat pump employing thermoacoustic technology is being developed for possible applications in households and offices. The desired temperature lift is from 10 °C to 80 °C. As a first step the heat pump is driven by a linear motor. Measurements and performance analysis of the heat pump are presented in this paper. The heat pump has a coefficient of performance which is the ratio of heat produced to the work input of 1.38 when operating between 10 °C to 80 °C. The performance relative to maximum possible Carnot value is 26.5%.

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Anomalous Increase in Specific Heat of Binary Molten Salt-Based Graphite Nanofluids for Thermal Energy Storage

Applied Sciences ◽

10.3390/app8081305 ◽

2018 ◽

Vol 8 (8) ◽

pp. 1305 ◽

Cited By ~ 6

Author(s):

Hyun Kim ◽

Byeongnam Jo

Keyword(s):

Specific Heat ◽

Molten Salt ◽

Base Fluid ◽

Solid Phase ◽

Layer Structure ◽

Synthesis Process ◽

Nanoparticle Concentration ◽

Anomalous Increase ◽

Salt Mixtures ◽

Graphite Nanoparticles

An anomalous increase of the specific heat was experimentally observed in molten salt nanofluids using a differential scanning calorimeter. Binary carbonate molten salt mixtures were used as a base fluid, and the base salts were doped with graphite nanoparticles. Specific heat measurements of the nanofluids were performed to examine the effects of the composition of two salts consisting of the base fluid. In addition, the effect of the nanoparticle concentration was investigated as the concentration of the graphite nanoparticles was varied from 0.025 to 1.0 wt %. Moreover, the dispersion homogeneity of the nanoparticles was explored by increasing amount of surfactant in the synthesis process of the molten salt nanofluids. The results showed that the specific heat of the nanofluid was enhanced by more than 30% in the liquid phase and by more than 36% in the solid phase at a nanoparticle concentration of 1 wt %. It was also observed that the concentration and the dispersion homogeneity of nanoparticles favorably affected the specific heat enhancement of the molten salt nanofluids. The dispersion status of graphite nanoparticles into the salt mixtures was visualized via scanning electron microscopy. The experimental results were explained according to the nanoparticle-induced compressed liquid layer structure of the molten salts.

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Experimental investigation on the influence of nano-fluids used as HTF in PCM based thermal energy storage system

Thermal Science ◽

10.2298/tsci191004060r ◽

2020 ◽

pp. 60-60

Author(s):

Krishna Reddy ◽

Meenakshi Reddy ◽

Durga Prasad

Keyword(s):

Stearic Acid ◽

Volume Concentration ◽

Storage System ◽

Energy Storage System ◽

Hot Water ◽

Paraffin Wax ◽

Nano Fluid ◽

Working Medium ◽

Thermal Energy Storage System ◽

Nano Fluids

The present study investigated the enhancement of energy conservation under the principles of pure substances that exercise phase change throughout charging and discharging processes. This work primarily focused on the thermal energy storage system, where the working medium charges the PCM?s namely (Paraffin wax & stearic acid) that is normally encapsulated in spherical balls. The potentiality in charging of working medium was examined upon blending HTF (heat transfer fluid) with four nano-particles (Al2O3, CuO, TiO2 & MgO). Several volume concentration levels (0.2%, 0.5% and 0.8%) were considered for afore mentioned nanoparticles under the influence of assumed flow rates (2l/min, 4l/min and 6l/min). The experiments were carried out with various nano-fluids used as HTF for different flow rates and volume concentrations. The results showed that there is a considerable amount of reduction in charging time, in case of 6 l/min, 0.8% volume concentration and PCM as Paraffin wax, around 27.22 % for TiO2 nano-fluid, 36.66% for Al2O3 nano-fluid, 40.90% for CuO nano-fluid and 63.63% for MgO nano-fluid, and PCM used as Stearic acid, around 26.31 % for TiO2 nano-fluid, 42.10% for Al2O3 nanofluid, 47.36% for CuO nano-fluid and 68.42% for MgO nano-fluid, when compared with the conventional HTF, water. From the results, it was observed that the effect of particle concentration played an important role in the heat transfer process. During the discharging process, 210 liters of hot water withdrawn with paraffin wax used as PCM and 198 liters of hot water withdrawn with stearic acid used as PCM.

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Use of Hydrogen and Fuel Cells for Refrigerated Transport

Handbook of Research on Advances and Applications in Refrigeration Systems and Technologies - Advances in Mechatronics and Mechanical Engineering ◽

10.4018/978-1-4666-8398-3.ch024 ◽

2015 ◽

pp. 881-924

Author(s):

Raquel Garde ◽

Sindia Casado ◽

Fernando Jimenez ◽

Gabriel Garcia-Naveda ◽

Monica Aguado

Keyword(s):

Fuel Cells ◽

Refrigeration System ◽

Road Transportation ◽

Performance Simulation ◽

The Road ◽

Operation Costs ◽

Transportation Sector ◽

Refrigerated Transport ◽

Reduced Costs ◽

And Performance

Benchmark refrigeration systems in the road transportation sector are powered by diesel, having operation costs of up to 6,000 €/y with the consequent increase of the goods cost. This chapter presents an alternative refrigeration system based on fuel cells (FC) and hydrogen as fuel, with higher efficiency, reduced costs and independent of diesel price fluctuations. Examples of the energy load profiles impact on the FC sizing, H2 consumption and system autonomy are presented as well as a description of the FC model and performance simulation results. The economical feasibility of this new refrigeration system linked to renewable energies is also analyzed and an economical assessment for different scenarios is presented.

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Experimental Analysis on Vapour Compression Refrigeration System Using Nanolubricant with HFC-134a Refrigerant

Nano Hybrids ◽

10.4028/www.scientific.net/nh.9.33 ◽

2015 ◽

Vol 9 ◽

pp. 33-43 ◽

Cited By ~ 6

Author(s):

A. Manoj Babu ◽

S. Nallusamy ◽

K. Rajan

Keyword(s):

Energy Consumption ◽

System Performance ◽

Mineral Oil ◽

Coefficient Of Performance ◽

Refrigeration System ◽

Hfc 134A ◽

Reduce Energy Consumption ◽

And Performance ◽

Vapour Compression ◽

Better Than

This paper investigates the reliability and performance of a refrigeration system using nanolubricant with 1, 1, 1, 2-Tetrafluoroethane (HFC-134a) refrigerant. Mineral Oil (MO) is mixed with nanoparticles such as Titanium Dioxide (TiO2) and Aluminium Oxide (Al2O3). These mixtures were used as the lubricant instead of Polyolester (POE) oil in the HFC-134a refrigeration system as HFC-134a does not compatible with raw mineral oil. An investigation was done on compatibility of mineral oil and nanoparticles mixture at 0.1 and 0.2 grams / litre with HFC-134a refrigerant. To carry out this investigation, an experimental setup was designed and fabricated in the lab. The refrigeration system performance with the nanolubricant was investigated by using energy consumption test. The results indicate that HFC-134a and mineral oil with above mentioned nanoparticles works normally and safely in the refrigeration system. The refrigeration system performance was better than the HFC-134a and POE oil system. Thus nanolubricant (Mixture of Mineral Oil (MO) and nanoParticles) can be used in refrigeration system to considerably reduce energy consumption and better Coefficient of Performance (COP).

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